Sandals constitute one of the earliest footwear known to man. Typically, sandals incorporate either a leather or rubberized sole which can be attached to the human foot by straps extending across the Achilles heel, and toes of the user. Early sandals were designed for walking. Sandals however, have been recently developed for more demanding sports-related activities. More force and stress is applied to the sole, during the running, stopping and twisting moves during sports activities such as golf, hiking, climbing, etc.
In order to increase traction, manufacturers of sandals used in sports activities have added lugs, spikes and cleats of both hard materials such as metal and plastic and soft, resilient materials such elastomers. Hard spikes and cleats can be dangerous to the user or to other involved in the sports activity, especially rough, contact sports. Another problem with spikes is that individually they sharply penetrate the turf and can rotate. They cannot be used on hard surfaces such as wood, blacktop or concrete and provide no cushioning on any surface. Some hard cleats prevent rotation but can still have pointed protrusions that can be dangerous.
Softer spikes have recently been introduced that are less punishing to fairways, greens and hard indoor surfaces. However, these spikes do not adequately prevent rotation and allow the sole to slide.
Resilient lugs and cleats for sandals have been adapted from athletic shoes such as basketball and tennis shoes to be used with sandals. The lugs and cleats are primarily designed to grip smooth surfaces such as wood floors or tennis courts. The cleats and lugs are positioned within the perimeter of the sole and usually are aligned parallel to the longitudinal axis of the sole. Cleats that are positioned at the perimeter usually face downwardly or outwardly from the portion of the upper adjacent the sole.
List of Prior References U.S. Pat. No. Patentee 1,070,951 Elliott 2,932,096 Tavormina 4,335,529 Badalamenti 4,404,759 Dassler 4,546,559 Dassler 4,635,383 Free 4,641,438 Laird, et al. 4,642,917 Ungar 4,741,114 Stubblefield 5,918,385 Sessa